The new core resource will build a competitive research base to facilitate collaborative projects which apply these complex databases to issues such as disparities in health care for the aged, cost of cancer treatment, and the influence of pre-existing co-morbidities on treatment decisions and outcomes. The specific aims of the core are to: 1) develop and maintain architecture for organizing database products for cancer control research at the interface of aging and cancer including computer programs, source data files, analysis files, variable dictionaries; and reports; 2) provide service and training to improve accessibility of the core databases; 3) develop new database linkages in support of pilot research projects; and 4) provide methodologic expertise for research proposals involving core databases.